Warning about metal dust caps !

[tookadum]

Dust caps - On another post, Kantara suggested that he may have put these on his bike.

In a past life I put some of these on a high performance bike - they looked the dogs! 

However, a few months later I tried to remove them to blow the tyres up and found I couldn't!! 

I took the bike to my friendly mechanic who advised me that sometimes the metal (aluminium) reacts with the metal on the tyre valve and binds!!  The result of this was I had to have both wheels removed, tyres took off and new valves fitted - add this to rebalancing the tyres etc. it was quite a costly exercise !

Before you put any metal valves on apply a slither of vaseline or grease to them to prevent them binding ! 

[advguy]

Your 100% right...on my last bike some mates thought it would be cute to put those valve stem lights on my bike that would glow pink then you moving  it was the last ride so i left them on over winter. Spring time they would not come off with plyers. I had to get a dremmel and cut them off. If you really love them use anti-seize on the thread

[Robell]

Yup, put a spot of copperslip on the threads.

Most metal caps will have decent seal in the top, whereas plastic ones probably won't.

[Kantara]

Thanks guys for the info ref metal dust caps.  I will get some copperslip.  Again many thanks.

[Umoth]

In my job before last I think I put in 5 warranty claims for the aluminium dust-caps seizing onto the (TPMS) valves, and the cars were less than a year old. Each TPMS valve was over £50, and in most cases the claim was for all 4 wheels.
The owners did not check their tyre pressures regularly as they did not need to, they had 'Tyre Pressure Monitoring System' (TPMS) on the car. By the time the car told them to blow up their tyres all 4 valve caps were seized solid.
Attempts by the manufacturer to pass the buck 'tyre pressures should be checked weekly, and if they were the valve caps would be removed weekly, and not seize' were quickly dismissed - 'the car has TPMS, the pressure is checked constantly, no need to remove the caps!'......

I am happy to keep my plastic caps, if they seize I can cut them off, and fit new plastic ones.

[Robell]

When I did Bikesafe, a few years ago, the police recommended metal caps with inbuilt seals.

They keep dirt out of the valve, but can also act as a seal to prevent air leakage, particularly at higher speeds, when the valve may be inclined to lift off it's seat.
Not sure how much this happens in practice, but they found a couple of metal caps from their own garage for me, before I left.

[Umoth]

Robell

{snip} particularly at higher speeds, when the valve may be inclined to lift off it's seat. {/snip}

I doubt that an Inazuma will ever go fast enough for that to be an issue, it can not go over 90Mph. At perhaps 150-200 Mph it might be worth considering.

[Robell]

 

Fair point - it just becomes a habit to fit decent caps 

[Kantara]

Robell

Yup, put a spot of copperslip on the thread.

Most metal caps will have decent seal in the top, whereas plastic ones probably won't.

Again thanks for the advise Robell.  I did mine yesterday.